Air conditioning apparatus



Nov. 17, 1936. R. H. ANDEFIEGG 2,061,447

AIR CONDITIONING APPARATUS Filed Sept. 23, 1955 4 Sheets-Sheet 1 INVENTZ;

ATTORNEY Nov. 17, 1936. R. H. ANDEREGG 2,061,447

AIR CONDITIONING APPARATUS 7 Filed Sept. 25, 1935 4 Sheets-Sheet 2 39 {II/4N7 4a 4a I 4 2 2 3a 37 4a 4a m n n n n m ATTORNEY 4 Sheets-Sheet 3 INVENTOR BY 6 A; A if;

ATTORNEY R. H. ANDEREGG Filed Sept. 25, 1955 AIR CONDITIONING APPARATUS Nov. 1.7, 1936.

Nov. 17, 1936.- A R. H. ANDEVREGG 2,061,447

' AIR CONDITIONING APPARATUS Filed Sept; 25, 1955 4 sheets-sheet 4 1 I62 102 I05 E1? Gig 7 11$ INVENTOR ATTORNEY Patented Nov. 17, 1936 UNITED STATES PATENT OFFICE AIR CONDITIONING APPARATUS Reuben H. Anderegg, La Crosse, Wis., assignor to The Trane Company, La Crosse, Wis.

Application September 23, 1935, Serial No. 41,762

' 10 Claims. (01. 62117) My invention relates to an air conditioning apparatus, particularly for railway cars, and one of the chief objects of my invention is to provide an improved apparatus to economically and efliciently extract heat from one side of an air conditioning heat cycle for use in air conditioning a railway car.

Another object of my invention is an air conditioning apparatus which can use lower head pressures in the condenser.

Another object of my invention is an improvement in extracting heat from the condenser side of a heat cycle to reduce the load on the compressor.

Another object of my invention is to control the operation of the compressor motor in co-operation with the apparatus extracting heat on the condenser side of the heat cycle.

The foregoing and many other specific features of my invention are set forth in the following specification, where I describe what I consider the preferred embodiments of my invention. These are illustrated in the accompanying drawings where-- Figure 1 is a longitudinal cross section of a railway car showing diagrammatically the arrangement of the air conditioning equipment.

Figure 2 is a plan view of the partitions in the water compartment.

Figure 3 is a cross section of Figure 2, taken on the lines 2-2.

Figure 4 is a plan view of the condenser cool- .ing compartment.

Figure 5 is a cross section of Figure 4, taken on the lines 44, and showing the pump and connections in dotted lines.

Figure 6 diagrammatically shows the electrical connections between the compressor 'motors, thermostats and condenser cooling equipment.

Figure"! is a plan view of condenser cooling compartment similar to Figure 4 and showing a modified form of my-invention.

Referring to Figures 1 to 5, inclusive, 20 is the duct system for conveying conditioned air into outlets 2! into the car compartment 22 to be cooled. The cooling coils 25 are mounted in the top of the car and are connected with a source of cold or cooling cycle by means of the pipes 26 and 21. 28 is a filter interposed in the air inlet 29. 30

is a compressor mounted in a compartment 3| supported from the bottom 32 of the car, which compressor is operated by a motor Hill. 24 is the liquid line from the compressor 33 to the wet condenser coil 34 located in the compartment 35,

where the liquid or gas is cooled and then forced through the pipe 21 through the expansion valve 36 to the coil 25.

The compartment 35 contains equipment to cool the condenser and is a metallic box capable of holding a considerable amount of water, to-wit: 5 150 gallons, and comprises side walls 39 and 4|, end walls 40 and 42 and bottom 23. In the bottom of the box or compartment 35 is located a drain 33,. Traversing the length and width of the compartment 35 are reinforcing bars 31 and 38, 10 respectively, which are attached to the side walls 39 and 4| and the end walls 40 and 42, at 43 and 44, 45 and 46, respectively, each of the bars being provided with a plurality of openings 41 on the bottom of the bar, so that there is formed in the 15 compartment 35 a plurality of small water compartments 48, each connected to the adjacent compartment. The height of the water is regulated so that when full it will be substantially the height of the bars 31 and 38 and that any 20,

excess over that amount will flow out the air inlet 49. This air inlet opens toward the side of the car to avoid the dust and dirt of the roadbed, and across the inlet is placed an air filter 50 of conventional design and the filter is securely at- 25 tached to the side wall 39 by clips or wing nuts 5| so that it can be easily removable and replaced at'maintenance points 'to allow inspection, introduction of water and, if necessary, removal of coil. The coil 34 is a conventional fin and tube 30 type coil comprising tubes 52 and fins 53 which are rectangular in shape.

The heat exchange tubes longitudinally lay in a longitudinal plane and the fins in a vertical plane, and on the ends and sides of the coil are 5 protective and supporting casings 54 and 55, attached to which are rigid support straps 55, attached to the fioor 32 of the car by removable bolts 51. When the coil 34 is mounted in the compartment 35, the tubes longitudinally will lie 40 in horizontal planes; the fins will be in vertical planes, while the bottom and top edge of the fins and the casing 52 will lie in a plane forming an oblique angle to the horizontal. Sprays 58 are connected and attached to a water supply 45 pipe 59, supported from the bottom of the car 32 by the strap 63 and in communication with the water pump 6| with an inlet pipe'62 leading to the pump from the bottom of the compartment 35. The water pump is direct connected to and 50 operated by the motor 63. The motor, 63 by means of the belt 64,- and pulleys 65 and 66, rotates the shaft 68 on which are mounted fans. 51 with suction inlet 69 above the water level in the compartment.

The fans 6'! draw the air 55 through the inlet past the sprays 58 and through the coil 34 in a diagonal direction; thence through the fan housing 10; then downward through a duct I Ileading downward through the compartment 35 to an 'air outlet 12 located in the bottom of the compartment 35 so that the air is discharged toward the roadbed, and on movement of the train a slight suction will be caused by passing air upon the inlet I2, thus aiding the'action of the fans 61. The air outlet I2 is protected by the screen I3 to prevent the entrance of rocks and small animals and foreign material.

The sprays 58 are mounted in the compartment 35 between the filter-50 or the air inlet 49, and the coils 34, and are so set that the water will be directedin a diagonal direction and against the fins 52 and 53. The air stream passing by the wetted fins and tubes will evaporate a portion of the water, thereby extracting heat from the fins and tubes in addition to the normal heat extraction caused by the passage of the air. What moisture is not evaporated will fall down into the water compartment to be repumped and resprayed over the coil 34. In operation, a tank holding substantially I50 gallons will last ten to twelve hours. At maintenance points the supply can be easily replenished by removing the filter 50 and putting in water by means of a hose. At the same time the coil 34 can be thoroughly flushed by the same stream of water.

Hitherto, in using dry air to cool the condenser in an air conditioning apparatus for a railway car,'it has been found that approximately 8000 c. f. m. of dry air is required, while in using air substantially saturated or at the wet bulb temperature, only 2500 c. f. m. is required, thereby reducing materially the horsepower required for the fans.

Also, hitherto, in using dry air, the head pressures in the condenser were frequently approximately 275 pounds with a condensing temperature of 145 to 150 F. due to the high temperature of the air caused by reflected and radiated heat from the roadbed. Frequently air temperatures of to F. dry bulb were encountered, resulting in a head pressure of 2'75 pounds and a condensing temperature of to F. The maximum wet bulb temperature in the United States is about 80 F., and using this air, to-wit: 80 F. wet bulb and 100 F., dry bulb, would produce a head pressure of approximately 150 to pounds, with a condensing temperature around 100 F. This results in a two-fold saving-first, a reduction in the head pressure will reduce the load on the compressor and, second, liquid with a condensing temperature of 100 will do more work than a liquid with a 150 condensing temperature when passed, through the expansion valve and expanded into a gas with a required temperature of 40 F.

the dry bulb and, consequently, the wet bulb temperature of the entering air by means of a coil 200 placed in the entering air. This coil is shown in Figure 7 and is connected to the water supply pipe 59 by pipe 20I at coil inlet 206. A valve 202 is interposed in pipe 59 to regulate the flow oi." water to the coilby varying the orifice. A further valve 203 is interposed in, the pipe 204 to similarly regulate the amount of spray water supplied. After going through the coil, the water is returned to the water compartment by means of the pipe 205 connected to the coiloutlet 201 2,061,447 Assuming an air condition of 120 dry bulb,

.80 F., which would be the temperature of the water entering the coil 200; and with entering air with a dry bulb of 120 F., wet bulb 80 F., and dewpoint 63 there would be obtained a leaving air temperature of 100 dry bulb, 75 wet bulb and 63 dewpoint. is to further condition the air to a lower wet bulb condition than could be obtained without the use of the coil 200, and thus effect further economies in compressor load, head pressures and condensation temperatures as explained above.-

Referring to Figure 6 showing the controls for the equipment hereinbefore set forth, numeral I00 represents a compressor motor, IN a power line, I02 a return power line, I03 a magnetic starter in line I0 I, I04 a resistance starter. Line I02 goes through magnetic starter and resistance starter I04 to compressor motor I00. I 05 represents a part of line I02 from magnetic starter I03 to time switch I06, whose function is to'close the circuit through the magnetic starter, which starts the compressor motor. This time switch is controlled by the pump pressure switch I0I, through the lines I08 and H0 and car thermostat switch arm II2. Interposed in the line I'08 is the pump pressure switch .I0'I. Line I09 is a continuation of line I08, and the line I09 runs to a car thermostat III,

The tendency of the spray now and line IIO runs from the car thermostat as a I I4 so that when the holding coil is energized by closing of thermostat III, the magnetic starter '6 starts the evaporator condenser motor '53. A mercury switch H8 is located in the bottom of the tank 35 and is controlled by a float responsive to the height of the water in the tank 35 so when the water is low enough to allow the float to drop, the switch arm II9 opens.

The mercury switch I I8 is a double pole switch H2 is a switch arm for the comprising arms H9 and Him. The arm H9 is connected by the line I20 leading from the holding coil H5 and the line I2I to the thermostat III; thence by the line I23 as a return power line, A further saving may be obtained by reducing andtthe switch arm I ISA is connected to the line IIOA, which is a returmpower line, and also by line I I0, which is connected to the thermostat I I I. When the switch I I8 is closed the circuits will be closed and the motor 63 will operate; and when the switch I I8 is open due to the fall of the water in the tank, the circuit formed by the lines I20,

I2I and I23 will be broken and the circuit formed by the line IIOA, 0', I09, holding coil I22 and line I08 will be broken. This will cause the time switch I00 to finally open as hereinafter set'torth and break the connection in the line II4A, thus taking the energy from the holding coil H5,

cuit represented by the lines I08, I09, IIO energizes the coil I22, causing time switch arms I25 to rotate into a position which closes the circuit represented by lines I05 and I26 energizing the coil I21 in the magnetic starter I03, which starts the compressor motor I00, which continues to run as long as the line is closed. When the switch arm I24 is open, the circuit is broken, coil I 22 is de-energized, thereby causing the time switch I06 to break the circuit to the compressor motor, thereby stopping it.

The time switch I06 is composed of two movable switch arms I25 and I21 so that when the coil I22 is energized, the arms I25 and I21 move to the left over an arc and contact the points I29 and I28, respectively, of the lines I26 and I05, respectively. And when coil I22 is de-energized, the switch arms move to'the. right, breaking the circuit formed by the lines I26 and I05.

On switch arm I21 is also a contact point I30, interconnected to line I I4 at contact point I3I.

As switch arms I25 and I21 move to the left, contact point I30 is brought in contact with are power line I I3 and return power line II4 through holding coil II5 of the magnetic starter II6.

Contact point I30 maintains contact with are I32 as long as switch arms I25 and I21 are movingto left and also maintains contact when switch arms I25 and I21 make contact with points I29 and I28; respectively.

When time switch arms I25 and I21 have moved to the left and closed contacts between switch arms I25 and I21, and contacts I29 and I28 respectively, any breaking of contact between switch arm II2 of car thermostat III and line I2I because of lowering of car temperature below "setting of thermostat, or any break in contact between switch arm H2 and line IIO because of lowering of car temperature below setting of thermostat, or any break in contact between switch arm I24 and line I08 in pressure switch I01 because of insufiicient pressure in discharge line of pump, or any break between switch arm H9 and line I20 in mercury switch II8 will deenergize coil I22 in time switch I 06, causing switch arms I25 and I21'to move to the right, thus breaking contact with contact points I29 and I28, respectively, and stopping compressor motor I by opening magnetic starter I03.

As switch arms I21 and I25 move to right, contact point I30 will maintain contact with are I 32 until contact arms I25 and I21 are in the extreme position at the right, when contact will be broken between contact point I30 and are Thus, holding coil II will remain energized through power lines H4 and H3 and contact point I30 and arc I32 until switch arms I25 and I21 are in the -extreme right position, when coil II5 wil1be de-ener'gized due to breaking of contact between point I30 and are I32. This magnetic starter II6 will continue to maintain in operation the evaporator condenser motor 63 after compressor motor I00 is stopped for the time required for switch arms I25 and I21 to move from extreme left position to extreme right position, where contact between points I30 and I32 is broken, coil I I5 is de-energized and evapo- I32, which completes the circuit through separate thermostats.

' ture and opening rator condenser motor 63 is stopped. As thermostat switch arm II2 again makes contact with lines H0 and I2I due to increase in car temperature, holding coil II5 of magnetic starter II6 will be energized starting evaporator condenser motor 63, which will close pressure switch arm I24 and line I08, thus energizing coil I22 which will cause switch arms I25 and I 21 to move to the left and start compressor motor I00 as described above. a I In case of shortage of water in evaporative condenser, switch arm I I9 will not make contact with line I20 and will not allow' car thermostat to start equipment, because current I20 to H4 through holding coil I I5 is broken.

Line I33 is a power line interconnected to line MI in magnetic switch I03 and resistances I34, I35 and I36 respectively. Resistances I34, I35 and I36 are connected in series by means of lines I31 and I38, respectively.

Line I38 is a continuation of power line I33 connecting resistance I36 to the field coil I40 of compressor motor I 00.

Line MI is a return power line from field coil I40 to continuation'of return power line I02.

By means of the thermostats I 42 and I43 and I44, and relay switches I45, I46 and I41, the resistances I34, I35 and I 36 are inserted in power lines I33 and I39, either singly .or in multiple to vary the speed of compressor motor I00 as follows.

Thermostat I42 is connected to power line I48, 7

power line I48 to line I38 through relay switch Thermostat I44 is connected to power line I 48 by line I59 through holding coil I60 of relay switch I41. Thermostat switch arm I6I is connected to return power line I5I by means of line I62.

Line I63 connects power line I48 to line I31 through relay switch I41.

In order to clarify control diagram, thermostats I42 and I43 and I44 have been shown as In actual practice thermostats I 42, I43 and,I44 would all be contained in one instrument.

Thermostats I42, I43 and I44 are of the heating type closing the circuit on lowering temperathe circuit on rising temperature. a

Thermostats I42, I 43 and I44 are set to operate in sequence-that is, thermostat I42 is set to open first on rising temperature and cut out last-on lowering temperature. Thermostat I43 will open second on a rising temperature and close second on lowering temperature. Thermostat I44 will open last on rising temperature and I34, I35 and I36, and to the field coil I46 thus decreasing the current to field coil I40 and increasing the speed of the motor I and compressor 30.

I64 is a starting shorting switch connected from line I33 by line I65 to return power line I39 by line I66. This starting switch is mechanically, connected with resistance starter I04 by arm I61 so that in starting, contact arm I68 will complete circuit through switch I64 and through starting coil III4, thus starting compressor motor I06 at same speed through all starting cycles. When compressor motor gets up to running speed, contact arm I68 is disconnected by mechanical arm I61 attached thereto, through resistance starter I04, exercising a magnetic attraction on the arm I61 similar to a solenoid. Thus, when the switch I64 is open, the speed of the compressor motor is dependent upon the action of the thermostats I42, I43 and I44.

While I have described the foregoingpreferred embodiments-of my invention, I contemplate that many changes may be made without departing from the scope or spirit of my invention.

I claim:

1. In an air conditioning apparatus for a railway car, the combination of a heat exchange cycle, with the evaporator side of said cycle situated within the car to condition the air therein, a compressor in said cycle delivering gas under pressure to the condenser side of said cycle, housed within a compartment beneath said car, said compartment having a water chamber, an air inlet,-a removable filter in said airinlet, an air outlet and means to draw air from said inlet to outlet, a condenser coil interposed in said condenser side and in the path of said .air, sprays positioned between said air inlet and said condenser coil, conduits connecting said sprays with the bottom of said water chamber, a pump in one of said conduits, a pressure switch in said conduit controlling the operation of said compressor, means to draw air from said inlet through said sprays and coil to said outlet.

2. In an air conditioning apparatus for a railway car, the combination of a heat exchange cycle, with the evaporator side of said cycle situated within the car to condition the air therein, a compressor in said cycle delivering gas under pressure to the condenser side of said cycle, housed within a, compartment beneath said car, said compartment having an air inlet and an air outlet and fan means to draw air from said inlet to outlet, a condenser coil interposed in said condenser side and in the path of said air, sprays positioned between said air inlet and said condenser coil, conduits connecting said sprays with the bottom of said water chamber, a pump in one of said conduits, a pressure switch in said conduit, means responsive to said pressure switch controlling the operation of said compressor.

3. In an air conditioning apparatus for a railway car, the combination of a heat exchange cycle, with the evaporator side of said cycle situated within the car to condition the air therein. a compressor in said cycle delivering gas under pressure to the condenser side of said cycle, housed within a compartment beneath said ear, said compartment having an air inlet and an air outlet and fan means to draw air from said inlet to outlet, a condenser coil interposed in said condenser side and in the path of said air, sprays positioned between said air inlet and said condenser coil, means to draw air from said inlet through said sprays and coil to said outlet, single means to operate both said pump and said fan, means responsive to the height of the water in water chamber controlling the operation of said fan and pump.

4. In an air conditioning apparatus for a railway car, the combination of a heat exchange cycle, with the evaporator side of said cycle situated within the car to condition the air therein, a compressor in said cycle delivering gas under pressure to the condenser side of said cycle, housed within a compartment beneath said car, said compartment having an air inlet and an air outlet and water chamber therein, a condenser coil interposed in said condense r'side and in the path of said air, sprays positioned between said air inlet and said condenser coil, conduits connecting said sprays with the bottom of said water chamber, a pump in one of said conduits, fan means to draw air from said inlet through said sprays and coil to said outlet, means responsive to air in said car controlling the operation of said compressor, means to continue the operation of said pump a predetermined length of time after said compressor has stopped, whereby the pressure in said condenser is decreased.

5. In an air conditioning apparatus for a railway car, the combination of a heat exchange cycle, with the evaporator side of said cycle situated within the car to condition the air therein, a compressor in said cycle delivering gas under pressure to the condenser side of said cycle, housed within a compartment.

beneath said bar, said compartment having an air inlet and an air outlet and water chamber therein, a condenser coil interposed in said condenser side and in the path of said air, sprays positioned between said air inlet and said condenser coil, conduits connecting said sprays with the bottom of said water chamber, a pump in one of said conduits, fan means to draw air from said inlet through said sprays and coil to said outlet, means responsive to air in said car controlling the operation of said compressor, means to insure the operation of said pump a predetermined time before the compressor starts and after itstops, whereby the pressure in said condenser is decreased.

6. In an air conditioning apparatus for a railway car, the combination of a heat ex-' change cycle, with the evaporator side of said cycle situated within the car to condition the air therein, a compressor insaid cycle delivering gas under pressure to the condenser side of said cycle, housed within a compartment beneath said car, said compartment having an air inlet and an air outlet and water chamber therein, a condenser coil interposed in said condenser side and in the path of said air, sprays positioned between said air inlet and said condenser coil, conduits connecting said sprays with the bottom of said water chamber, a pump in one of said conduits, means to draw air from said inlet through said sprays and coil to said outlet, means to stop said compressor responsive tov the height of water in said water compartment.

7. In an air conditioning apparatus for a railway car, the combination of a heat exchange cycle, with the evaporator side of said cycle situated within the car to condition the air therein, a compressor in said cycle delivering gas under pressure to the condenser side of said cycle, housed within a compartment beneath said car, said compartment having an air inlet and an air outlet and fan means to draw 2,001,447 I l a air from said. inlet to outlet, a condenser coil interposed in said condenser side and in the path of said air, sprays positioned between said air inlet and said condenser coil, means to'draw air from said inlet through said sprays and coil to said outlet, single means to operate both said pump and said fan, and means to pre-cool said air before entering said sprays.

8. In an air conditioning apparatus for a railway car, the combination of a heat exchange cycle, with the evaporator side of said cycle situated within the car to condition the air therein, a compressor in said cycle delivering gas under pressure to the condenser side of said cycle, housed within a compartment beneath said car, said compartment having an air inlet and an air outlet and water chamber therein, a condenser coil interposed in said condenser side and in the path of said air, sprays positionedbetween said air inlet and said condenser coil, conduits connecting said sprays with the bottom of said water chamber, a pump in one of said conduits, fan means to draw air from said inlet through said sprays and coil to said outlet, and means to start the operation of the fan means and pump before the compressor starts to decrease the pressure in said condenser.

9. In an air conditioning apparatus for a rail:

- inlet and an air outlet and water chamber therein, a condenser'coil interposed in said condenser side and in the 'path of said air, sprays positioned between said air inlet and said ,con-

40 denser coil, conduits connecting said sprays with the bottom of said water chamber, a pump in one of said conduits, means responsive to the height of the'water in the water chamber controlling the operation of said fan means and pump said compartment for drawing air therethrough and exhausting it therefrom, a motor for driving said air pump, a water pump also driven by said motor, adapted to draw water from a low point in said compartment and discharge it as spray in the air space therein, a condenser coil located in said air space in the path of air drawn therethrough and of the spray so discharged by said water, pump, a float operated switch in said compartment for controlling said pump motor in accordance with the water level, a pressure operated switch for said motor controlled by the pressure of water circulated by said pump, and a thermostat in circuitwith said pump motor for controlling the operation of the same in accordance with the temperature requirements of the car to be cooled, ,a compressor motor controlled by a time switch in circuit with said pump motor for actuating the compressor of a refrigerating apparatus carried by the car, said time switch serving to close the compressor motor circuit after the pump motor circuit has been completed by closing of the aforesaid switches in circuit therewith, and adapted to be opened when contact is broken by any of said switches or by said thermostat, prior to deenergization of the said pump motor circuit and cessation of pump motor operation. 

